Amputation, once the mainstay of treatment of malignant bone tumors, now is used selectively and infrequently. Most patients are candidates for limb-sparing procedures because of effective chemotherapeutic agents and regimens, improved imaging modalities, and advances in reconstructive surgery. Patient age as well as tumor location and extent of disease help define the most appropriate surgical alternatives. Options for skeletal reconstruction include modular endoprostheses, osteoarticular or bulk allografts, allograft-prosthetic composites, vascularized bone grafts, arthrodesis, expandable prostheses, rotationplasty, and limb-lengthening techniques. Two key factors must be considered: survival rates should be no worse than those associated with amputation, and the reconstructed limb must provide satisfactory function. Functional outcome studies comparing limb-sparing procedures and amputation have inherent limitations, including the inability to randomize treatment and the subjective nature of important outcome measures.